build: Add AX_CHECK_COMPILE_FLAG command
build: Add AX_CHECK_COMPILE_FLAG command

Import AX_CHECK_COMPILE_FLAG from autoconf archives

Signed-off-by: Ola Jeppsson <793f970c52ded1276b9264c742f19d1888cbaf73@adapteva.com>

debug-de-su-ka/pal,Adamszk/pal3,mateunho/pal,Adamszk/pal3,RafaelRMA/pal,eliteraspberries/pal,olajep/pal,aolofsson/pal,8l/pal,mateunho/pal,mateunho/pal,Adamszk/pal3,debug-de-su-ka/pal,debug-de-su-ka/pal,eliteraspberries/pal,mateunho/pal,parallella/pal,RafaelRMA/pal,Adamszk/pal3,eliteraspberries/pal,olajep/pal,olajep/pal,mateunho/pal,parallella/pal,parallella/pal,eliteraspberries/pal,olajep/pal,8l/pal,RafaelRMA/pal,debug-de-su-ka/pal,aolofsson/pal,8l/pal,8l/pal,aolofsson/pal,debug-de-su-ka/pal,parallella/pal,eliteraspberries/pal,parallella/pal,aolofsson/pal,RafaelRMA/pal